JP3236717B2 - Thermal transfer image receiving sheet - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal transfer image receiving sheet, and more particularly to a thermal transfer image receiving sheet having excellent surface smoothness and concealment.

[0002]

2. Description of the Related Art Conventionally, when an output print of a computer or a word processor is performed by a thermal sublimation transfer method, a thermal transfer sheet having a dye layer provided on one surface of a substrate sheet has been used. This thermal transfer sheet includes a base sheet having heat resistance and a dye layer formed by applying and drying an ink obtained by mixing a sublimable dye with a binder on the base sheet. Then, heat is applied from the back side of the thermal transfer sheet by the thermal head to transfer a large number of three or four color dots to the material to be transferred, thereby forming a full-color image. The formed image is clear and excellent in transparency because the coloring material used is a dye, has high reproducibility and gradation of intermediate colors, and can form high-quality images equivalent to conventional full-color photographic images. .

However, it is impossible to form a high-quality image as described above on a transfer material having no dye-dying property, such as ordinary plain paper, and the like. A thermal transfer image receiving sheet having a dye receiving layer formed on the sheet in advance is used.

[0004]

As a substrate sheet used in the above-mentioned thermal transfer image-receiving sheet, plain paper is preferred from the viewpoint of texture, but a thermal transfer image-receiving sheet having a dye receiving layer formed only on one side of plain paper is preferred. The sheet is liable to be curled (so-called moisture-absorbing curl) under the influence of the environmental humidity, and there is a problem that the transport trouble in the printer frequently occurs.
In addition, there is a problem that paper discharge troubles frequently occur due to the occurrence of curl after printing due to heat reception during printing.

To solve such a problem, Japanese Patent Laid-Open Publication No.
Japanese Patent Application Laid-Open No. 2-198497 proposes that a substrate provided with a receiving layer is provided with a core material and a synthetic paper adhered thereon to prevent curling of a sheet after image formation. Has been made.

However, in this case, when paper is used as the core material, the formation of the paper does not appear on the surface of the sheet, the appearance and the surface smoothness are deteriorated, and the printing is adversely affected. there were. In addition, when an ordinary transparent plastic is simply used and an adhesive layer considering only ordinary adhesion is used, there is a disadvantage that the concealing property is insufficient and the commercial value is reduced.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide a heat transfer image-receiving sheet having excellent appearance, surface smoothness, and concealability.

[0008]

In order to achieve the above object, the present invention provides a thermal transfer image receiving sheet comprising a base sheet and a dye receiving layer provided on one surface of the base sheet. The substrate sheet includes a core substrate, and synthetic paper laminated on at least one surface of the core substrate via an adhesive layer, wherein the core substrate is formed of a resin film, The layer was configured to contain a resin binder and a white pigment.

[0009]

The base sheet constituting the thermal transfer image-receiving sheet comprises a core base and a synthetic paper laminated on at least one surface of the core base via an adhesive layer, wherein the core base comprises a resin film. Since the adhesive layer is formed so as to contain a resin binder and a white pigment, the adhesive layer is particularly excellent in appearance, surface smoothness, and concealment.

[0010]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic sectional view of the thermal transfer image-receiving sheet of the present invention. In FIG. 1, a thermal transfer image receiving sheet 1 includes a base sheet 2 and a dye receiving layer 3 formed on one surface of the base sheet 2.

The base sheet 2 has a core base 21 and a synthetic paper 22 laminated on one surface of the core base 21 with an adhesive layer 28 interposed therebetween. The dye receiving layer 3 is formed on the synthetic paper 22.

The core substrate 21 is made of a resin film. Specifically, a polypropylene film, a polyethylene film, a polyester film, a polycarbonate film, a polyethylene naphthalate film, a polyetheretherketone film, a polyamide film, a polyethersulfone film, etc. The material is not particularly limited, but those having high smoothness on the film surface are desirable. In the present application, since the whiteness is imparted by the adhesive layer, an opaque film having low transparency and low whiteness can be used.

The thickness of the core substrate 21 is 5 to 20.
It is about 0 μm.

Such a core base material 21 and a synthetic paper 2 described later
2 includes a resin binder and a white pigment.

The resin binder is not particularly limited as long as it has an adhesive function. For example, urethane-based adhesive resin, polyolefin-based adhesive resin, polyester-based adhesive resin, acrylic-based adhesive resin, epoxy-based adhesive And the like.

Examples of the white pigment contained in such a resin binder include inorganic pigments such as titanium oxide, silicon oxide, magnesium carbonate, barium sulfate, zinc oxide, talc, clay, polystyrene, melamine, acrylic, and the like.
Organic fillers such as organic silicones are exemplified. As the particle size of these fillers, without lowering the adhesive strength,
In addition, a particle size that does not affect the surface shape, that is, 5
Those having a size of μm or less are preferred.

The white pigment is used in an amount of 10 to 400 parts by weight, more preferably 10 to 400 parts by weight in terms of solids, based on 100 parts by weight of the remaining components excluding the white pigment in the adhesive layer 28.
It is contained in an amount of 0 to 200 parts by weight. When this value exceeds 400 parts by weight, there is a disadvantage that the adhesiveness is insufficient. On the other hand, when this value is less than 10 parts by weight, there is a disadvantage that the concealing property becomes insufficient. .

The thickness of the adhesive layer 28 is small, and is usually about 0.5 to 10 μm.

The core substrate 21 is provided with the adhesive layer 28 interposed therebetween.
The synthetic paper 22 provided thereon is made of a synthetic paper such as a polyolefin-based, polystyrene-based, or polyester-based synthetic paper, and is particularly preferably a synthetic paper provided with a paper-like layer containing fine pores. The fine pores in the paper-like layer can be formed, for example, by stretching a synthetic resin in a state containing a fine filler. The thermal transfer image-receiving sheet provided with such a paper-like layer has an effect that, when an image is formed by thermal transfer, the image density is high and the image does not vary. This is because the fine pores have a heat insulating effect, and the thermal energy efficiency is good, and the good cushioning property due to the fine pores is provided on the synthetic paper, which is considered to contribute to the receiving layer on which an image is formed. .

Specific examples of the synthetic paper include commercially available synthetic paper “Yupo” (manufactured by Oji Yuka Synthetic Paper) and Toyopearl S
S (manufactured by Toyobo Co., Ltd.), Wallispar (manufactured by Toyobo Co., Ltd.), W-900 (manufactured by Diafoil Hoechst Co., Ltd.) and the like. As the synthetic paper, a so-called foamed single-layer plastic film such as a foamed polypropylene sheet or foamed polyester can be used.

The thickness of the synthetic paper 22 is 5 to 20.
It is about 0 μm.

As a method of joining the synthetic paper 22 and the core substrate 21 via the adhesive layer 28, for example, a so-called dry lamination, non-solvent lamination, extruding the adhesive layer with an extruder, and then laminating. The EC lamination method is exemplified.

The dye receiving layer 3 provided on the sheet substrate 2 thus laminated is for receiving the sublimable dye migrating from the thermal transfer sheet and maintaining the formed image. .

Examples of the resin for forming the dye receiving layer 3 include polyolefin resins such as polypropylene,
Halogenated polymers such as polyvinyl chloride and polyvinylidene chloride; vinyl polymers such as polyvinyl acetate and polyacrylic ester; polyester resins such as polyethylene terephthalate and polybutylene terephthalate; polystyrene resins; polyamide resins; and ethylene and propylene. Examples include copolymer resins of olefins and other vinyl monomers, ionomers, cellulose resins such as cellulose diacetate, polycarbonates, and the like, and particularly preferred are vinyl resins and polyester resins.

The dye receiving layer 3 is formed by dissolving the above resin in a solvent, applying the solution by air knife coating, reverse coating, gravure coating or wire bar coating, and then drying.

The thermal transfer image receiving sheet of the present invention may have an intermediate layer formed between the base sheet 2 and the dye receiving layer 3. Such an intermediate layer is for improving the adhesion between the base sheet 2 and the dye receiving layer 3, and can be formed of a polyurethane resin, an acrylic resin, a polyethylene resin, a polypropylene resin, an epoxy resin, or the like. The thickness is preferably about 0.1 to 25 μm.

A bubble-containing layer may be provided between the base sheet 2 and the above-mentioned intermediate layer. This bubble-containing layer can be formed using a foaming agent, and the foaming agent used is dinitropentamethylenetetramine, diazoaminobenzene, azobisisobenzene, which decomposes by heat to generate gases such as oxygen, carbon dioxide, and nitrogen. Decomposition-type foaming agents such as butyronitrile and azodicarbonamide; and microballoons in which a low-boiling liquid such as butane and pentane is microencapsulated with a resin such as polyvinylidene chloride and polyacrylonitrile.

Further, an antistatic agent may be added to the dye receiving layer 3. The antistatic agent to be used is a known antistatic agent, for example, a quaternary ammonium salt, a cationic antistatic agent such as a polyamine derivative, an anionic antistatic agent such as an alkyl phosphate, and a nonionic antistatic agent such as a fatty acid ester. Is mentioned.

Further, a so-called back coat layer may be provided on the back side of the base sheet 2 in order to make it suitable for paper supply or discharge. An example of the back coat layer includes an antistatic layer containing the above antistatic agent.

FIG. 2 shows a modified example of the base sheet 2 of the thermal transfer image-receiving sheet 1.
1 on the back surface side further through an adhesive layer 29.
have. The adhesive layer 29 is basically made of the same composition as the adhesive layer 28 described above. However, when the adhesive layer 28 contains a white pigment, the adhesive layer 29 does not necessarily require a white pigment. . Conversely, a mode in which a white pigment is contained only in the adhesive layer 29 is of course also possible. Even if both of the adhesive layers 28 and 29 contain a white pigment, the synthetic paper 23 described above may be basically used as the synthetic paper 23.

Next, the present invention will be described in more detail with reference to specific examples and comparative examples. (Example 1) As a core substrate of a substrate sheet, a thickness of 60 μm
Polyester film (Lumilar S14, Toray Industries, Inc.)
Was prepared.

On this core substrate, synthetic paper (Toyobo Co., Ltd.)
(Trade name, manufactured by Toyopearl SS P4255, thickness: 35 μm) was bonded and laminated using an adhesive layer composition having the following composition to prepare a base sheet of Example 1. The thickness of the adhesive layer after drying was 3 μm.

Adhesive layer composition / Polyurethane adhesive: Deck Dry LX703 (Dai Nippon Ink Co., Ltd.) 15 parts by weight Curing agent: Deck Dry KP 90 (Dai Nippon Ink Co., Ltd.) 1 Parts by weight ・ Titanium oxide: Taipaque CR-50 (manufactured by Ishihara Sangyo Co., Ltd.) 15 parts by weight ・ Ethyl acetate 15 parts by weight Next, the surface of the synthetic paper of the base sheet 2 is used for a receiving layer having the following composition. The coating liquid was applied by a bar coater (at the time of drying, thickness: 10 μm), temporarily dried by a drier, and dried in an oven at 100 ° C. for 30 minutes to form a dye receiving layer.
Was obtained.

Composition of coating solution for receiving layer Polyester resin (Vylon 200, manufactured by Toyobo Co., Ltd.) 20 parts by weight Silicone oil (X22-3050C, manufactured by Shin-Etsu Chemical Co., Ltd.) 2 weights Parts: Silicone oil (X22-3000E, manufactured by Shin-Etsu Chemical Co., Ltd.) 2 parts by weight Toluene 80 parts by weight (Example 2) The core substrate of the substrate sheet of Example 1 was applied to a thickness of 60 μm. Was changed to a polypropylene film (Pyren film OT P2161, manufactured by Toyobo Co., Ltd.), and the adhesive layer composition of Example 1 was changed to the following adhesive layer composition. Otherwise, the procedure of Example 1 was repeated to prepare a thermal transfer image-receiving sheet of Example 2.

Adhesive layer composition / Polyurethane adhesive: Deck Dry LX703 (Dai Nippon Ink Co., Ltd.) 15 parts by weight Curing agent: Deck Dry KP 90 (Dai Nippon Ink Co., Ltd.) 1 Parts by weight-Zinc oxide: Zinc Hua No. 1 (manufactured by Sakai Chemical Co., Ltd.) ... 15 parts by weight-Ethyl acetate ... 15 parts by weight (Example 3) A polycarbonate film having a thickness of 200 μm (Iupilon, manufactured by Mitsubishi Gas Chemical Co., Ltd.) was used, and the adhesive layer composition of Example 1 was changed to the following adhesive layer composition.
Otherwise, the procedure of Example 1 was repeated to prepare a thermal transfer image-receiving sheet of Example 3.

Adhesive layer composition / Polyurethane adhesive: Deck Dry LX703 (Dai Nippon Ink Co., Ltd.) 15 parts by weight Curing agent: Deck Dry KP 90 (Dai Nippon Ink Co., Ltd.) 1 Parts by weight Barium sulfate (manufactured by Sakai Chemical Industry Co., Ltd.): 15 parts by weight Ethyl acetate: 15 parts by weight (Example 4) Titanium oxide which is a white pigment in the adhesive layer composition of Example 1 described above: Taipaque The content of CR-50 was changed to 2.0 parts by weight. Otherwise, the procedure of Example 1 was repeated to prepare a thermal transfer image-receiving sheet of Example 4. (Example 5) The content of titanium oxide: Taipe CR-50 as a white pigment in the adhesive layer composition of Example 1 was adjusted to 6
Changed to 0 parts by weight. Otherwise, the procedure of Example 1 was repeated to prepare a thermal transfer image-receiving sheet of Example 5. (Example 6) In the adhesive layer composition of Example 1, the content of titanium oxide: Taipe CR-50, which is a white pigment, was adjusted to 2
Changed to 0 parts by weight. Otherwise, the procedure of Example 1 was repeated to prepare a thermal transfer image-receiving sheet of Example 6. (Comparative Example 1) Titanium oxide (Taipec CR-50) as a white pigment was removed from the adhesive layer composition of Example 1 above. Otherwise, Comparative Example 1 was performed in the same manner as in Example 1 above.
Was produced. (Comparative Example 2) The polyester film (Lumirror S14, manufactured by Toray Industries, Inc.) having a thickness of 60 μm as the core substrate used in Comparative Example 1 was manufactured by Kanzaki Paper Co., Ltd., with a new top of 72.3 g / g. It was changed to m ^2. Otherwise, Comparative Example 1 above
In the same manner as in Example 1, a thermal transfer image-receiving sheet of Comparative Example 2 was produced.

The thermal transfer image-receiving sheets (Examples 1 to 6, Comparative Examples 1 and 2) produced as described above were evaluated as follows.

Evaluation item (1) Surface smoothness The surface smoothness of the thermal transfer image-receiving sheet was visually judged.

(2) Printing Condition Printing the entire surface of the dye receiving layer with solid black (Printer UP50
00, manufactured by Sony Corporation), and the print condition was visually judged.

(3) Concealment Black solid print (printer UP5000, SO
NY (manufactured by NY Co., Ltd.) was placed below, and each sample was placed on the printed matter to determine whether or not it was visible through. Those that cannot be seen through are good.

The results are shown in Table 1 below.

[0043]

[Table 1]

[0044]

The effects of the present invention are clear from the above results. That is, the base sheet of the thermal transfer image-receiving sheet according to the present invention includes a core substrate and a synthetic paper laminated on at least one surface of the core substrate via an adhesive layer, and the core substrate is Since the adhesive layer is made of a resin film and contains a resin binder and a white pigment, it has excellent effects in appearance, surface smoothness, and concealment.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of a thermal transfer image receiving sheet of the present invention.

FIG. 2 is a schematic sectional view of another thermal transfer image receiving sheet of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Thermal transfer image-receiving sheet 2 ... Base sheet 21 ... Core base material 22, 23 ... Synthetic paper 28, 29 ... Adhesive layer 3 ... Dye receiving layer

Continuation of front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B41M 5/38-5/40

Claims (2)

(57) [Claims] 1. A thermal transfer image-receiving sheet comprising a base sheet and a dye-receiving layer provided on one surface of the base sheet, wherein the base sheet is a core base, and the core base is Comprising a synthetic paper laminated on at least one side of the adhesive layer via an adhesive layer, the core substrate is made of a resin film, the adhesive layer contains a resin binder and a white pigment, the white pigment is bonded Component 100 excluding white pigment in the layer
A thermal transfer image-receiving sheet, which is contained in an amount of 10 to 400 parts by weight based on part by weight (solid content). 2. The white pigment includes titanium oxide, silicon oxide, magnesium carbonate, barium sulfate, zinc oxide, talc, clay inorganic pigment, polystyrene, melamine,
The thermal transfer image-receiving sheet according to claim 1, wherein the thermal transfer image-receiving sheet is at least one selected from an acrylic filler and an organic silicone-based organic filler.